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Updated: Jun 8, 2025

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
Light, Switch, Action! The Influence of Geometrical Photoisomerization in an Adaptive Self-Assembled System
Marco Ovalle1, Charlotte N Stindt1, Ben L Feringa1
1Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 3, Groningen 9747 AG, The Netherlands.
Abstract:
The ubiquitous ability of natural dynamic nanostructures to adapt to environmental changes is a highly desirable property for chemical systems, particularly in the development of complex matter, molecular machines, and life-like materials. Designing such systems is challenging due to the generation of complex mixtures with responses that are difficult to predict, characterize, and diversify. Here, we navigate between self-assembled architectures using light by operating an intrinsic photoswitchable building block that governs the state of the system. When complementary units are present, the photoswitch determines the predominant architecture, reversibly adapting between the cage and macrocycles, including (otherwise inaccessible) higher-energy assemblies. Our study showcases this concept with seven different transformations, offering an unprecedented degree of control, diversification, and adaptation by self-selecting complementary units. These findings could enable applications of on-demand dissipative macrocycles based on dynamic bonds. We also envision different transient nanostructures, e.g., reticular and polymeric materials, being explored by fine-tuning the nature of the complementary unit.
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